Setting: Material Blend Mode: "Alpha Blend" - A strange discovery

2.93.6
Eevee.

Hi.

I’m working on an animation that has an “Image As Plane” JPG of a room in a house.

In front of that Image, there are transparent PNGs of Christmas decorations.

Everything was OK until… I moved the camera to a new position.

One of the Christmas decoration PNGs DISAPPEARED.

I discovered that the Material setting “Blend Mode” for the background JPG had been set to “Alpha Blend”. (The JPG, obviously, has no alpha channel) “Opaque” solved the issue.

So… other than telling me that I’m stupid… does anyone have thoughts about this?

I think in eevee that setting has to be changed to get any transparency in the material.
Also this:
https://docs.blender.org/manual/en/3.1/render/eevee/materials/settings.html#blend-mode